Device and method for making dental resin-infiltrated ceramic material

Abstract

The present invention provides a device and method for manufacturing a dental resin-infiltrated ceramic material. The device comprises a raw material storage unit, a raw material pressurizing unit, an infiltration unit and a vacuum unit connected in sequence; the infiltration unit comprises an infiltration chamber; the infiltration chamber is divided into an upper vacuum chamber and a lower high-pressure chamber; the vacuum chamber and the high-pressure chamber are separated by a perforated partition; the high-pressure chamber is used to place a porous ceramic material; the device is divided into a vacuum chamber and a high-pressure chamber by a perforated partition, the porous ceramic material is placed in the high-pressure chamber, and the resin is fully filled in the micropores of the porous ceramic material by the dual effects of high pressure and vacuum, thereby improving the infiltration effect, shortening the infiltration time to less than 5 minutes, and improving the mechanical properties of the resin-infiltrated ceramic material, so that the bending strength of the obtained resin-infiltrated ceramic material reaches more than 240MPa, and the fracture toughness reaches 4.6MPa·m 1 / 2 The above has good application prospects.

Description

Technical Field

[0001] The invention belongs to the technical field of dental restorations, and in particular relates to a device and a method for manufacturing dental resin-infiltrated ceramic materials. Background Art

[0002] Dental resin composites were commercialized for anterior tooth restoration in the mid-1960s. With the development of dental restoration materials, in order to optimize the performance of resin composite restoration materials, digital technology based on computer-aided design and computer-aided manufacturing (CAD / CAM) has attracted the attention of many researchers to the combination of ceramic and resin composites, which is called "polymer infiltrated ceramic network (PICN)". This PICN material with good machinability has aroused the research interest of many people. Since the PICN composite material has a double mesh structure, composed of a ceramic skeleton and composite resin infiltration, it has both the flexibility of resin materials and the rigidity of ceramic materials. It has a structure and mechanical properties similar to natural teeth and has become a hot topic of concern.

[0003] The current mainstream resin infiltration ceramic process is to soak half or all of the porous ceramics modified by silane coupling agent after firing in the infiltration resin monomer to which the initiator is added, and remove the air in the ceramic block through vacuum negative pressure and capillary action to make the resin monomer rise along the micropores to complete the resin infiltration into the ceramic. However, due to the small micropores of porous ceramics, high resin viscosity, and low vacuum and capillary force, the resin infiltration results are poor and the efficiency is low. Therefore, this method requires repeated impregnation and vacuuming, and the production efficiency is low.

[0004] CN108524291A discloses a method for preparing a resin-infiltrated silicate composite material, which uses cold isostatic pressing to assist resin infiltration, attempting to open the closed pores generated in the ceramic block during the sintering process, and improve the transparency and aesthetic properties of the resin-infiltrated silicate composite material. The maximum bending strength of the composite material is about 200MPa. However, it still has certain problems: using cold isostatic pressing to assist resin infiltration, the pressure is applied from the periphery to the center at the same time, and there is no gas exhaust channel, which is not conducive to the removal of gas inside the composite resin ceramic.

[0005] In summary, how to provide a method for improving resin penetration efficiency and penetration quality has become a problem that needs to be solved urgently. Summary of the invention

[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a device and method for making dental resin-infiltrated ceramic materials. The device optimizes the structure of the infiltration chamber and utilizes the cooperation of a pressurizing unit and a vacuum unit to effectively shorten the resin infiltration time while ensuring the infiltration quality, and has good application prospects.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides an apparatus for making a dental resin-infiltrated ceramic material, the apparatus comprising a raw material storage unit, a raw material pressurizing unit, an infiltration unit, and a vacuum unit connected in sequence;

[0009] The osmosis unit includes an osmosis chamber;

[0010] The permeation chamber is divided into an upper vacuum chamber and a lower high-pressure chamber; the vacuum chamber and the high-pressure chamber are separated by a perforated partition;

[0011] The high pressure chamber is used for placing porous ceramic materials.

[0012] In the present invention, the device divides the infiltration chamber into a vacuum chamber and a high-pressure chamber by a perforated partition, the porous ceramic material is placed in the high-pressure chamber, and the resin is introduced into the high-pressure chamber by a pressurizing unit. Under the dual effects of the lower high pressure and the upper vacuum, the resin can be fully filled into the micropores of the porous ceramic material, thereby improving the infiltration effect, shortening the infiltration time, and enhancing the mechanical properties of the resin-infiltrated ceramic material, which is beneficial to production and application.

[0013] The following are preferred technical solutions of the present invention, but are not intended to be limitations of the technical solutions provided by the present invention. Through the following technical solutions, the technical objectives and beneficial effects of the present invention can be better achieved and realized.

[0014] As a preferred technical solution of the present invention, the permeation unit is also connected to the raw material storage unit.

[0015] Preferably, the raw material storage unit comprises a first storage tank and a second storage tank, which are used to store the silane coupling agent and the composite resin respectively.

[0016] Preferably, the vacuum chamber is independently connected to each raw material storage tank.

[0017] As a preferred technical solution of the present invention, the raw material pressurizing unit includes a pressurizing pump, and the pressurizing pump is connected to the high-pressure chamber.

[0018] As a preferred technical solution of the present invention, a heater is provided in the high-pressure chamber.

[0019] In the present invention, at least one heater is provided, preferably more than two heaters are evenly distributed on the side wall of the high pressure chamber to ensure the heating effect.

[0020] As a preferred technical solution of the present invention, the porous ceramic material is in block shape.

[0021] Preferably, the perforated partition plate is provided with at least one positioning hole, and each positioning hole corresponds to a piece of porous ceramic material.

[0022] Preferably, the opening size of each positioning hole is smaller than the size of the upper surface of the corresponding porous ceramic material.

[0023] Preferably, the opening contour of each of the positioning holes is 0.2-2 mm smaller than the upper surface contour of the corresponding porous ceramic material, for example 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1.0 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm or 2 mm, etc., but is not limited to the listed values, and other unlisted values ​​within this numerical range are also applicable.

[0024] As a preferred technical solution of the present invention, a sealing layer is provided on the lower surface of the perforated partition.

[0025] Preferably, the sealing layer comprises a rubber sealing layer.

[0026] As a preferred technical solution of the present invention, the vacuum unit includes a vacuum pump, and the vacuum pump is connected to the top of the vacuum chamber.

[0027] In a second aspect, the present invention provides a method for making a dental resin-infiltrated ceramic material, the method being performed using the apparatus described in the first aspect, the method comprising:

[0028] (1) placing a plurality of ceramic materials in the high-voltage chamber so that the ceramic materials correspond to the positioning holes of the perforated partition plate; then, installing and fixing the perforated partition plate;

[0029] (2) Evacuate the vacuum chamber;

[0030] (3) introducing a silane coupling agent into the high pressure chamber, stopping after a first set time, and then performing vacuum drying to obtain a modified ceramic porous ceramic material;

[0031] (4) then placing the modified multi-ceramic material in the high-pressure chamber so that it corresponds to the positioning hole of the perforated partition plate; then, installing and fixing the perforated partition plate;

[0032] (5) Evacuate the vacuum chamber;

[0033] (6) Resin is introduced into the high pressure chamber and stopped after a second set time is reached to obtain a dental resin-infiltrated ceramic material.

[0034] In the present invention, two sets of devices are used, one set of devices is used for modification operation, and the other set of devices is used for resin penetration operation.

[0035] As a preferred technical solution of the present invention, after the vacuuming in step (2), the vacuum pressure is below -0.05MPa, for example, -0.05MPa, -0.06MPa, -0.07MPa, -0.08MPa, -0.095MPa or -0.1MPa, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0036] Preferably, the first set time in step (3) is 1-5 minutes, such as 1 minute, 2 minutes, 3 minutes, 4 minutes or 5 minutes, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0037] Preferably, the vacuum drying temperature in step (3) is 80-150°C, for example 80°C, 90°C, 120°C, 110°C, 120°C, 130°C or 150°C, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0038] As a preferred technical solution of the present invention, in step (4), after the perforated partition is installed and fixed, heating is turned on.

[0039] Preferably, the heating temperature is 30-100°C, for example 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C or 100°C, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0040] Preferably, after the vacuuming in step (5), the vacuum pressure is below -0.05 MPa, for example -0.05 MPa, -0.06 MPa, -0.07 MPa, -0.08 MPa, -0.09 MPa or -0.1 MPa, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0041] Preferably, in step (6), a pressure pump is used to introduce the resin into the high-pressure chamber.

[0042] Preferably, the output pressure of the pressure pump is not less than 0.2 MPa, for example 0.2 MPa, 0.4 MPa, 0.6 MPa, 0.8 MPa, 1.0 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 7 MPa, 8 MPa, 9 MPa or 10 MPa, etc., but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0043] In the present invention, the infiltration resin is a composite resin. The resin monomer includes, but is not limited to, one or a combination of at least two of ethylenically unsaturated compounds such as acrylate, methacrylate, hydroxyl-functionalized acrylate or hydroxyl-functionalized methacrylate; and also includes polymerizable resin monomers such as polyethylene glycol dimethacrylate (PEGDMA), bisphenol A-glycidyl dimethacrylate (Bis-GM A), urethane dimethacrylate (U DMA), triethylene glycol dimethacrylate (TEGDMA), ethoxybisphenol A dimethacrylate (Bis-EMA6), hydroxyethyl methacrylate (HEMA) or bisphenol A epoxy resin.

[0044] Furthermore, the method for preparing the dental resin-infiltrated ceramic material specifically comprises:

[0045] S101, semi-wet ball milling the water-quenched lithium disilicate glass particles, sieving once every hour, collecting powders with a particle size between 200 mesh and 300 mesh, mixing with a PVA binder with a concentration of 0.5wt%-2wt%, semi-dry pressing, the pressure is between 2-8MPa, the pressure holding time is 30-180s, and then isostatic pressing is performed at 50-120MPa for 60-120s, and then standing at room temperature for 1-24h; then putting them into a degumming furnace for degumming, controlling the temperature to 400-500℃, and the time to 4-24h; when the furnace temperature drops by 200℃, taking out the degummed blocks, and the degumming must be sufficient to prevent the residual glue from carbonizing;

[0046] Put the debonded block into the sintering furnace for two-stage sintering. During the first stage of sintering, the heating rate is controlled at 5-30℃ / min, and the temperature is raised to 600-640℃ and kept for 60-180min; during the second stage of sintering, the heating rate is controlled at 20-50℃ / min, and the temperature is raised to 720-810℃ and kept for 10-50min; when the temperature drops to about 300℃, take out the ceramic block;

[0047] S102, mixing water and ethanol solution with a silane coupling agent in a volume ratio of 1:1, and adding acetic acid dropwise to adjust the pH to 3-4 to prepare a silane solution;

[0048] The porous ceramic block purged with compressed air is placed at a designated position in the high-pressure chamber, and the perforated partition is compacted and installed and fixed; the vacuum pump is turned on to control the vacuum pressure to be below -0.05MPa, and the booster pump is started to adjust the frequency to 10-20Hz. The silane coupling agent passes through the bottom and side wall of the ceramic block under the hydraulic pressure and the top vacuum, and the solution fully infiltrates the porous ceramic material for 1-5min. The power is turned off, and the ceramic block is taken out and vacuum dried at 80-150°C to obtain a modified porous ceramic material;

[0049] S103, clean the infiltration chamber, then place the modified porous ceramic material at the specified position of the high-pressure chamber 32, compact the perforated partition 33, and install and fix it; turn on the vacuum pump, control the vacuum pressure to below -0.05MPa, and turn on the heating to control the temperature to 30-100°C; then start the booster pump and adjust the frequency to 10-40Hz, and under the action of hydraulic pressure and top vacuum, the composite resin solution fully infiltrates the modified porous ceramic material for 3-5 minutes, turn off the power, obtain the dental resin infiltrated ceramic material, and immediately wrap it with PE film.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] The device of the present invention is divided into a vacuum chamber and a high-pressure chamber by a perforated partition. The porous ceramic material is placed in the high-pressure chamber. The dual effects of high pressure and vacuum are used to fully fill the micropores of the porous ceramic material with resin, thereby improving the infiltration effect, shortening the infiltration time to less than 5 minutes, and improving the mechanical properties of the resin-infiltrated ceramic material. The bending strength of the obtained resin-infiltrated ceramic material reaches more than 240MPa, and the fracture toughness reaches 4.6MPa·m 1 / 2 The above has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 It is a structural schematic diagram of a device for manufacturing dental resin-infiltrated ceramic material provided by a specific embodiment of the present invention.

[0053] Figure 2 This is a cross-sectional view of an infiltration chamber in a device for making a dental resin-infiltrated ceramic material provided in Example 1 of the present invention.

[0054] Among them, 1-raw material storage unit, 11-first storage tank, 12-second storage tank, 2-raw material pressurizing unit, 3-permeation unit, 31-vacuum chamber, 32-high pressure chamber, 33-perforated partition, 331-positioning hole, 34-sealing layer, 35-heater, 4-vacuum unit, 5-porous ceramic material. DETAILED DESCRIPTION

[0055] In order to better illustrate the present invention and facilitate understanding of the technical solution of the present invention, the present invention is further described in detail below. However, the following embodiments are only simple examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims.

[0056] In a specific embodiment, the present invention provides a device for making a dental resin-infiltrated ceramic material, the structural schematic diagram of the device is as follows: Figure 1 shown.

[0057] The device comprises a raw material storage unit 1, a raw material pressurizing unit 2, a permeation unit 3 and a vacuum unit 4 connected in sequence;

[0058] The permeation unit 3 includes a permeation chamber; the cross-sectional view of the permeation chamber is as shown in Figure 2 shown.

[0059] The permeation chamber is divided into an upper vacuum chamber 31 and a lower high-pressure chamber 32; the vacuum chamber 31 and the high-pressure chamber 32 are separated by a perforated partition 33;

[0060] The high pressure chamber 32 is used to place the porous ceramic material 5 .

[0061] Furthermore, the vacuum chamber 31 is connected to the raw material storage unit 1; the raw material storage unit 1 includes a first storage tank 11 and a second storage tank 12; the vacuum chamber 31 is independently connected to each raw material storage tank.

[0062] Furthermore, the raw material pressurizing unit 2 includes a pressurizing pump, and the pressurizing pump is connected to the high-pressure chamber 32 .

[0063] Furthermore, a heater 35 is disposed in the high pressure chamber 32 .

[0064] Further, the porous ceramic material 5 is in block shape;

[0065] The perforated partition plate 33 is provided with at least one positioning hole 331, and each positioning hole 331 corresponds to a piece of porous ceramic material 5;

[0066] The opening size of each positioning hole 331 is smaller than the upper surface size of the corresponding porous ceramic material 5;

[0067] The opening profile of each positioning hole 331 is 0.2-2 mm smaller than the upper surface profile of the corresponding porous ceramic material 5 .

[0068] Furthermore, a sealing layer 34 is provided on the lower surface of the perforated partition plate 33; the sealing layer 34 includes a rubber sealing layer.

[0069] Furthermore, the vacuum unit 4 includes a vacuum pump, and the vacuum pump is connected to the top of the vacuum chamber 31 .

[0070] In a specific embodiment, the present invention also provides a composite resin, and the preparation method of the composite resin includes: first adding the initiator BPO (benzoyl peroxide) to the diluent TEGDMA, using an electric stirrer to stir at 300r / min for 5h to ensure that the BPO particles are completely dissolved; then adding the resin matrix Bis-GMA, controlling the stirring speed to 120r / min, stirring for 8h, and obtaining the Bis-GMA / TEGDMA composite resin.

[0071] In a specific embodiment, the present invention also provides a method for making a dental resin-infiltrated ceramic material, the method comprising the following steps:

[0072] S101, semi-wet ball milling the water-quenched lithium disilicate glass particles, sieving once every hour, collecting powders with a particle size between 200 mesh and 300 mesh, mixing with a PVA binder with a concentration of 1wt%, semi-dry pressing, the pressure is between 5MPa, the pressure holding time is 100min, and then isostatic pressing is performed at 80MPa for 90s, and then standing at room temperature for 10h; then putting them into a degumming furnace for degumming, controlling the temperature to 450°C, and the time to 14h; when the furnace temperature drops by 200°C, taking out the degummed blocks, and the degumming must be sufficient to prevent the residual glue from carbonizing;

[0073] The debonded block is placed in a sintering furnace for two-stage sintering. During the first stage of sintering, the heating rate is controlled at 15°C / min, and the temperature is raised to 620°C and kept for 120 minutes; during the second stage of sintering, the heating rate is controlled at 35°C / min, and the temperature is raised to 760°C and kept for 30 minutes; when the temperature drops to about 300°C, the ceramic block is taken out;

[0074] S102, mixing water and ethanol solution with a silane coupling agent in a volume ratio of 1:1, and adding acetic acid dropwise to adjust the pH to 3.5 to prepare a silane solution;

[0075] The porous ceramic block purged with compressed air is placed in a fixed position of the high-pressure chamber 32, and the perforated partition 33 is compacted and installed and fixed; the vacuum pump is turned on to control the vacuum pressure to -0.08MPa; then the booster pump is turned on to adjust the frequency to 15Hz, and the silane coupling agent passes through the bottom and side wall of the ceramic block under the hydraulic pressure and the top vacuum, and the solution fully infiltrates the porous ceramic material 5 for 3min, and the power is turned off, and the ceramic block is taken out and vacuum dried at 100°C to obtain a modified porous ceramic material;

[0076] S103, clean the infiltration chamber, then place the modified porous ceramic material at the specified position of the high-pressure chamber 32, compact the perforated partition 33, and install and fix it; turn on the vacuum pump, control the vacuum pressure to below -0.05MPa, and turn on the heating to control the temperature to 30-100°C; then start the booster pump and adjust the frequency to 10-40Hz, and under the action of hydraulic pressure and top vacuum, the Bis-GMA / TEGDMA composite resin solution fully infiltrates the modified porous ceramic material for 3-5 minutes, turn off the power, obtain the dental resin infiltrated ceramic material, and immediately wrap it with PE film.

[0077] The following are typical but non-limiting embodiments of the present invention:

[0078] Embodiment 1:

[0079] This embodiment provides a device for making a dental resin-infiltrated ceramic material, the device is based on the device in the specific embodiment, wherein:

[0080] The porous ceramic material 5 is a modified porous ceramic material and is in the shape of a rectangular parallelepiped, one of which has a size of 18 mm×15 mm×13 mm (length×width×height);

[0081] There are six positioning holes 331 on the perforated partition plate 33, and they are rectangular, corresponding to one of the opening dimensions of the above-mentioned ceramic block, which is 17.6 mm×14.6 mm (length×width).

[0082] Application Examples 1-6 of the present invention respectively provide a method for preparing a dental resin-infiltrated ceramic material, and the methods are all performed using the device described in Example 1, and the methods are all based on the method for preparing a dental resin-infiltrated ceramic material in a specific implementation manner, wherein the process conditions of S101 and S102 remain unchanged, and the process parameters involved in S103 are specifically shown in Table 1.

[0083] Table 1

[0084]

[0085] Comparative Example Application Example 1

[0086] This comparative application example provides a method for making a dental resin-infiltrated ceramic material, the method comprising:

[0087] The modified porous ceramic material obtained in S102 of the specific implementation method is placed in a container filled with the configured Bis-GMA / TEGDMA composite resin, and the height of the composite resin submerging the modified porous ceramic material is 1 / 2. The container is then placed in a vacuum device, and the vacuum pressure is controlled to be -0.1MPa. The vacuuming is stopped after 40 minutes, and it can be seen that there are white areas in the modified porous ceramic material that are not completely penetrated; the vacuum is drawn again, and after 40 minutes, there are still white areas that are not completely penetrated; the vacuum is drawn again until the modified porous ceramic material is completely penetrated, which takes a total of 200 minutes.

[0088] The dental resin-infiltrated ceramic materials obtained in Application Examples 1-6 and Comparative Example 1 were cured at 100°C for 16 hours, and strength bars and fracture toughness bars were cut out with an internal circle slicer. After grinding and polishing, the bending strength and fracture toughness were tested with a tensile testing machine. The results are shown in Table 2.

[0089] Table 2

[0090]

[0091] By using the device described in Examples 1-6 of the present invention and the method described in Application Examples 1-6, the infiltration time can be controlled within 5 minutes, and the mechanical properties of the material can be further improved, so that the bending strength reaches more than 240 MPa and the fracture toughness reaches 4.6 MPa·m 1 / 2 Compared with the conventional method (i.e. comparative application example 1), the above method greatly shortens the infiltration time, improves the production efficiency, and has a good application prospect.

[0092] The present invention illustrates the device and detailed method of the present invention through the above embodiments, but the present invention is not limited to the above devices and detailed methods, that is, it does not mean that the present invention must rely on the above devices and detailed methods to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the operation of the present invention, addition of auxiliary operations, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A device for making dental resin-infiltrated ceramic material, characterized in that: The device comprises a raw material storage unit, a raw material pressurizing unit, a permeation unit and a vacuum unit connected in sequence; The osmosis unit includes an osmosis chamber; The permeation chamber is divided into an upper vacuum chamber and a lower high-pressure chamber; the vacuum chamber and the high-pressure chamber are separated by a perforated partition; The high-pressure chamber is used to place porous ceramic materials; a heater is arranged in the high-pressure chamber; The raw material pressurizing unit includes a pressurizing pump, and the pressurizing pump is connected to the high-pressure chamber; The perforated partition plate is provided with at least one positioning hole, and each positioning hole corresponds to a piece of porous ceramic material; The vacuum unit comprises a vacuum pump, and the vacuum pump is connected to the top of the vacuum chamber; The porous ceramic material is in block shape; The opening size of each positioning hole is smaller than the size of the upper surface of the corresponding porous ceramic material.

2. The device according to claim 1, characterized in that The permeation unit is also connected to the raw material storage unit.

3. The device according to claim 2, characterized in that The raw material storage unit includes a first storage tank and a second storage tank.

4. The device according to claim 3, characterized in that The vacuum chamber is independently connected to each raw material storage tank.

5. The device according to claim 1, characterized in that The opening profile of each positioning hole is 0.2-2 mm smaller than the upper surface profile of the corresponding porous ceramic material.

6. The device according to claim 1, characterized in that A sealing layer is provided on the lower surface of the perforated partition plate.

7. The device according to claim 6, characterized in that The sealing layer comprises a rubber sealing layer.

8. A method for producing a dental resin-infiltrated ceramic material, characterized in that: The method is performed using the device according to any one of claims 1 to 7, and the method comprises: (1) placing a plurality of ceramic materials in the high-voltage chamber so that the ceramic materials correspond to the positioning holes of the perforated partition plate; then, installing and fixing the perforated partition plate; (2) Evacuate the vacuum chamber; (3) introducing a silane coupling agent into the high-pressure chamber, stopping after a first set time, and then performing vacuum drying to obtain a modified porous ceramic material; (4) then placing the modified multi-ceramic material in the high-pressure chamber so that it corresponds to the positioning hole of the perforated partition plate; then, installing and fixing the perforated partition plate; (5) Evacuate the vacuum chamber; (6) Resin is introduced into the high pressure chamber and stopped after a second set time is reached to obtain a dental resin-infiltrated ceramic material.

9. The method according to claim 8, characterized in that After the vacuuming in step (2), the vacuum pressure is below -0.05 MPa.

10. The method according to claim 8, characterized in that The first set time in step (3) is 1-10 minutes.

11. The method according to claim 8, characterized in that The vacuum drying temperature in step (3) is 80-150°C.

12. The method according to claim 8, characterized in that Step (4) After the perforated partition is installed and fixed, heating is turned on.

13. The method according to claim 12, characterized in that The heating temperature is 30-100°C.

14. The method according to claim 8, characterized in that After the vacuuming in step (5), the vacuum pressure is below -0.05 MPa.

15. The method according to claim 8, characterized in that In step (6), a pressure pump is used to introduce resin into the high-pressure chamber.

16. The method according to claim 15, characterized in that The output pressure of the booster pump is not less than 0.2 MPa.

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